Methods and systems for forming slots in a semiconductor substrate

ABSTRACT

The described embodiments relate to methods and systems of forming slots in a semiconductor substrate. In one exemplary embodiment, a slot is formed by cutting with a disk into a semiconductor substrate into one of a first and second surfaces. A trench is created in the semiconductor substrate into the other of the first and second surfaces to form in combination with said cutting a slot through the substrate.

BACKGROUND OF THE INVENTION

[0001] Inkjet printers have become ubiquitous in society. These printersprovide many desirable characteristics at an affordable price. However,the desire for ever more features at ever-lower prices continues topress manufacturers to improve efficiencies. Consumers want ever higherprint image resolution, realistic colors, and increased pages ofprinting per minute. One way of achieving consumer demands is byimproving the print head and its method of manufacture. Currently, theprint head is time consuming and costly to make.

[0002] Accordingly, the present invention arose out of a desire toprovide fast and economical methods for forming print heads and otherfluid ejecting devices having desirable characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS

[0003] The same components are used throughout the drawings to referencelike features and components.

[0004]FIG. 1 is a front elevational view of an exemplary printer.

[0005]FIG. 2 is a block diagram that illustrates various components ofan exemplary printer.

[0006]FIG. 3 is a perspective view of a print carriage in accordancewith one exemplary embodiment.

[0007]FIG. 4 is a perspective view of a print carriage in accordancewith one exemplary embodiment.

[0008]FIG. 5 is a perspective view of a print cartridge in accordancewith one exemplary embodiment.

[0009]FIG. 6 is a cross-sectional view of a print cartridge inaccordance with one exemplary embodiment.

[0010]FIG. 7 is a top view of a print head in accordance with oneexemplary embodiment.

[0011]FIGS. 8a-8 e show a cross-sectional view of a substrate inaccordance with one exemplary embodiment.

[0012]FIGS. 9a-9 f show a cross-sectional view of a substrate inaccordance with one exemplary embodiment.

[0013]FIGS. 10a-10 d show a cross-sectional view of a substrate inaccordance with one exemplary embodiment.

[0014]FIGS. 11a-11 e show a cross-sectional view of a substrate inaccordance with one exemplary embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Overview

[0016] The embodiments described below pertain to methods and systemsfor forming slots in a semiconductor substrate. One embodiment of thisprocess will be described in the context of forming fluid feed slots ina print head die substrate. As commonly used in print head dies, thesemiconductor substrate often has microelectronics incorporated within,deposited over, and/or supported by the substrate. The fluid feedslot(s) allow fluid to be supplied to fluid ejecting elements containedin ejection chambers within the print head. The fluid ejection elementscommonly comprise heating elements or firing resistors that heat fluidor fluid causing increased pressure in the ejection chamber. A portionof that fluid can be ejected through a firing nozzle with the ejectedfluid being replaced by fluid from the fluid feed slot.

[0017] The fluid feed slot can be made in various ways. In one exemplaryembodiment, a slot can be formed by making a saw cut from one side orsurface of the substrate. This exemplary embodiment can also removematerial from a side opposite the first side using various removaltechniques. The combination of cutting and removing can form a slotthrough the substrate in some embodiments. Slots made this way can bevery narrow and as long as desired. Narrow slots remove less materialand have beneficial strength characteristics that can reduce diefragility. This, in turn, can allow slots to be positioned closertogether on the die.

[0018] Although exemplary embodiments described herein are described inthe context of providing dies for use in inkjet printers, it isrecognized and understood that the techniques described herein can beapplicable to other applications where slots are desired to be formed ina substrate.

[0019] The various components described below may not be illustratedaccurately as far as their size is concerned. Rather, the includedfigures are intended as diagrammatic representations to illustrate tothe reader various inventive principles that are described herein.

[0020] Exemplary Printer System

[0021]FIG. 1 shows one embodiment of a printer 100, embodied in the formof an inkjet printer. The printer 100 can be, but need not be,representative of an inkjet printer series manufactured by theHewlett-Packard Company under the trademark “DeskJet”. The inkjetprinter 100 is capable of printing in black-and-white and/or in color.The term “printer” refers to any type of printer or printing device thatejects fluid or other pigmented materials onto a print media. Though aninkjet printer is shown for exemplary purposes, it is noted that aspectsof the described embodiments can be implemented in other forms ofprinting devices that employ inkjet printing elements or other fluidejecting devices, such as facsimile machines, photocopiers, and thelike.

[0022]FIG. 2 illustrates various components in one embodiment of printer100 that can be utilized to implement the inventive techniques describedherein. Printer 100 can include one or more processors 102. Theprocessor 102 controls various printer operations, such as mediahandling and carriage movement for linear positioning of the print headover a print media (e.g., paper, transparency, etc.).

[0023] Printer 100 can have an electrically erasable programmableread-only memory (EEPROM) 104, ROM 106 (non-erasable), and/or a randomaccess memory (RAM) 108. Although printer 100 is illustrated having anEEPROM 104 and ROM 106, a particular printer may only include one of thememory components. Additionally, although not shown, a system bustypically connects the various components within the printing device100.

[0024] The printer 100 can also have a firmware component 110 that isimplemented as a permanent memory module stored on ROM 106, in oneembodiment. The firmware 110 is programmed and tested like software, andis distributed with the printer 100. The firmware 110 can be implementedto coordinate operations of the hardware within printer 100 and containsprogramming constructs used to perform such operations.

[0025] In this embodiment, processor(s) 102 process various instructionsto control the operation of the printer 100 and to communicate withother electronic and computing devices. The memory components, EEPROM104, ROM 106, and RAM 108, store various information and/or data such asconfiguration information, fonts, templates, data being printed, andmenu structure information. Although not shown in this embodiment, aparticular printer can also include a flash memory device in place of orin addition to EEPROM 104 and ROM 106.

[0026] Printer 100 can also include a disk drive 112, a networkinterface 114, and a serial/parallel interface 116 as shown in theembodiment of FIG. 2. Disk drive 112 provides additional storage fordata being printed or other information maintained by the printer 100.Although printer 100 is illustrated having both RAM 108 and a disk drive112, a particular printer may include either RAM 108 or disk drive 112,depending on the storage needs of the printer. For example, aninexpensive printer may include a small amount of RAM 108 and no diskdrive 112, thereby reducing the manufacturing cost of the printer.

[0027] Network interface 114 provides a connection between printer 100and a data communication network in the embodiment shown. The networkinterface 114 allows devices coupled to a common data communicationnetwork to send print jobs, menu data, and other information to printer100 via the network. Similarly, serial/parallel interface 116 provides adata communication path directly between printer 100 and anotherelectronic or computing device. Although printer 100 is illustratedhaving a network interface 114 and serial/parallel interface 116, aparticular printer may only include one interface component.

[0028] Printer 100 can also include a user interface and menu browser118, and a display panel 120 as shown in the embodiment of FIG. 2. Theuser interface and menu browser 118 allows a user of the printer 100 tonavigate the printer's menu structure. User interface 118 can beindicators or a series of buttons, switches, or other selectablecontrols that are manipulated by a user of the printer. Display panel120 is a graphical display that provides information regarding thestatus of the printer 100 and the current options available to a userthrough the menu structure.

[0029] This embodiment of printer 100 also includes a print engine 124that includes mechanisms arranged to selectively apply fluid (e.g.,liquid ink) to a print media such as paper, plastic, fabric, and thelike in accordance with print data corresponding to a print job.

[0030] The print engine 124 can comprise a print carriage 140. The printcarriage can contain one or more print cartridges 142. In one exemplaryembodiment, the print cartridge 142 can comprise a print head 144 and aprint cartridge body 146. Additionally, the print engine can compriseone or more fluid sources 148 for providing fluid to the printcartridges and ultimately to a print media via the print heads.

[0031] Exemplary Embodiments and Methods

[0032]FIGS. 3 and 4 show exemplary print cartridges (142 a and 142 b) ina print carriage 140. The print carriages depicted are configured tohold four print cartridges although only one print cartridge is shown.Many other exemplary configurations are possible. FIG. 3 shows the printcartridge 142 a configured for an up connect to a fluid source 148 a,while FIG. 4 shows print cartridge 142 b configured to down connect to afluid source 148 b. Other exemplary configurations are possibleincluding but not limited the print cartridge having its ownself-contained fluid supply.

[0033]FIG. 5 shows an exemplary print cartridge 142. The print cartridgeis comprised of the print head 144 and the cartridge body 146. Otherexemplary configurations will be recognized by those of skill in theart.

[0034]FIG. 6 shows a cross-sectional representation of a portion of theexemplary print cartridge 142 taken along line a-a in FIG. 5. It showsthe cartridge body 146 containing fluid 602 for supply to the print head144. In this embodiment, the print cartridge is configured to supply onecolor of fluid to the print head. In this embodiment, a number ofdifferent fluid feed slots are provided, with three exemplary slotsbeing shown at 604 a, 604 b, and 604 c. Other exemplary embodiments candivide the fluid supply so that each of the three fluid feed slots 604a-604 c receives a separate fluid supply. Other exemplary print headscan utilize less or more slots than the three shown here.

[0035] The various fluid feed slots pass through portions of a substrate606 in this embodiment. Silicon can be a suitable substrate, for thisembodiment. In some embodiments, substrate 606 comprises a crystallinesubstrate such as single crystalline silicon or polycrystalline silicon.Examples of other suitable substrates include, among others, galliumarsenide, glass, silica, ceramics or a semi conducting material. Thesubstrate can comprise various configurations as will be recognized byone of skill in the art. In this exemplary embodiment, the substratecomprises a base layer, shown here as silicon substrate 608. The siliconsubstrate has a first surface 610 and a second surface 612. Positionedabove the silicon substrate are the independently controllable fluiddrop generators that in this embodiment comprise firing resistors 614.In this exemplary embodiment, the resistors are part of a stack of thinfilm layers on top of the silicon substrate 608. The thin film layerscan further comprise a barrier layer 616. The barrier layer cancomprise, among other things, a photo-resist polymer substrate. Abovethe barrier layer is an orifice plate 618 that can comprise, but is notlimited to a nickel substrate. The orifice plate has a plurality ofnozzles 619 through which fluid heated by the various resistors can beejected for printing on a print media (not shown). The various layerscan be formed, deposited, or attached upon the preceding layers. Theconfiguration given here is but one possible configuration. For example,in an alternative embodiment, the orifice plate and barrier layer areintegral.

[0036] The exemplary print cartridge shown in FIGS. 5 and 6 is upsidedown from the common orientation during usage. When positioned for use,fluid can flow from the cartridge body 146 into one or more of the slots604 a-604 c. From the slots, the fluid can travel through a fluid feedpassageway 620 that leads to a firing chamber 622. A firing chamber canbe comprised of a firing resistor, a nozzle, and a given volume of spacetherein. Other configurations are also possible. When an electricalcurrent is passed through the resistor in a given firing chamber, thefluid can be heated to its boiling point so that it expands to eject aportion of the fluid from the nozzle 619. The ejected fluid can then bereplaced by additional fluid from the fluid feed passageway 620.

[0037] The embodiment of FIG. 7 shows a view from above the thin-filmsurface of a substrate incorporated into a print head. The substrate iscovered by the orifice plate 618 with underlying structures of the printhead indicated in dashed lines in this embodiment. The orifice plate isshown with numerous nozzles 619. Below each nozzle lies the firingchamber 622 that is connected to a fluid feed passageway (feed channel)620 and then to slot 604 a-c. Slot 604 a has indicated generallyopposing sidewalls 602 a and 602 b and end walls 604 a and 604 b. Theslots are illustrated in this embodiment as an elliptical configurationwhen viewed from above the first surface of the substrate. Otherexemplary geometries include rectangular among others.

[0038] Exemplary Slot Forming Techniques

[0039]FIGS. 8a-11 e show exemplary embodiments that remove portions ofthe substrate to form fluid feed slots through the substrate. The Figs.represent a portion of cross-sections taken along line b-b indicated inFIG. 7. The Figs. show a mechanical cutting tool 800. In these exemplaryembodiments, the cutting tool can comprise a circular cutting disk orsaw 802. Other exemplary embodiments can utilize various reciprocatingor vibrating saws among others. The exemplary slotting techniquesdescribed above and below can be implemented manually and/or can beautomated.

[0040] In the present embodiment, as depicted in FIG. 8a, the circularsaw 802 can have a generally planar surface 804 that is orientedgenerally perpendicular to the first surface 610 of the substrate 606.This can be seen for example in FIG. 8a where the saw revolves around anorigin or axis of rotation 806 that extends into and out of the page.The circular saw is capable of spinning in a clockwise orcounterclockwise direction about the axis of rotation. Other suitableembodiments can spin in one direction and reverse to spin in the otherdirection or a combination thereof. Suitable saws can have a bladecomprising diamond grit, or other suitable material. Suitable circularsaws can be obtained from Disco and KNS, among others. Exemplary sawblades can have diameters ranging from less than about ¼ of an inch tomore than to inches. One particular embodiment uses a saw blade having adiameter of about ½ inch.

[0041]FIG. 8a shows the circular saw 802 positioned above the substrateso that the saw can be lowered along the −y-axis to contact thesubstrate. Various substrates can be utilized, with exemplaryembodiments having thicknesses ranging from less than 100 microns tomore than 2000 microns. In this exemplary embodiment, the substrate isremoved by the mechanical cutting action of the saw, other methods ofremoving substrate will be discussed below. The saw can continue to belowered through the substrate to a desired depth. The cut made by thisvertical movement of the saw is commonly called a chop or plunge cut.

[0042]FIG. 8b shows an exemplary embodiment where the saw has beenlowered along the −y-axis so as to pass all of the way through a portionof the substrate 606. It will be noted that, in this embodiment, thoughthe saw has passed through the substrate, the axis of rotation 806 hasnot contacted or been extended to a position within the substrate. Otherembodiments can have other orientations.

[0043]FIG. 8c shows the result of the cutting when the saw blade isremoved from the substrate. The cut is defined by two generally parallelsidewalls 702 a and 702 b (shown FIG. 7) connected or joined by a firstend wall 704 a and a second end wall 704 b (shown FIG. 7 and FIG. 8c).End wall 704 a has a first surface 810 and end wall 704 b has a secondsurface 812.

[0044]FIG. 8d shows a second chop cut being made into the substratestarting at the second surface 612. FIG. 8e shows the resultant slotupon completion of the second chop cut. Each of the end walls of theslot now has two surfaces. End wall 704 a is defined by surface 810 fromthe first cut and surface 814 from the second cut. End wall 704 b hassurface 812 from the first cut and surface 816 from the second cut. Inthis exemplary embodiment, each of the surfaces 810-816 is curved orarched. Other exemplary configuration will be described below.

[0045] The described surfaces 810 and 814 meet to form an angle θrelative to the substrate 606. Similarly, surfaces 812 and 816 meet toform an angle δ relative to the substrate. In some exemplaryembodiments, these angles can be equal to or greater than 90 degrees.Maintaining such an angle can increase the strength of the resultantsubstrate as compared to other configurations. By increasing thestrength of the substrate, slots can be positioned closer together whichcan decrease material costs of production. The increased substratestrength can also decrease production costs associated with die breakageduring assembly.

[0046] Other features of the described embodiments can also provideimproved substrates over existing technologies. For example, in someexemplary embodiments, the saw can make a cut where the distance betweenthe sidewalls is less than about 30 microns. Other exemplary embodimentsutilize saw cut widths up to 200 or more microns.

[0047] Such narrow slots have a high aspect ratio, where the aspectratio is the thickness of the substrate divided by the width of theslot. The configurations of some embodiments can have aspect ratios fromgreater than or equal to 1 to greater than or equal to about 22. Withone particular embodiment having an aspect ratio of about 3. The highaspect ratio slots of the exemplary embodiments can allow fluid feedslots to be formed that remove less substrate material and thereforeallow slots to be places closer together on the substrate withoutweakening the substrate. Print head dies utilizing such substrates canbe more compact, stronger, and cheaper to produce.

[0048] Additionally, cuts and/or slots made in the substrate with thecircular saw can have cleaner side edges with less chipping than otherslotting techniques. For example, slots made with the circular saw canhave chips in the sidewalls in the range of about 5-10 microns, whereasexisting sand drilling technology can create chips in excess of about45-50 microns. This feature in addition to the increased substratestrength can further allow slots to be placed closer together on thesubstrate than existing technologies.

[0049]FIGS. 9a-9 f show another exemplary embodiment for making slot(s)in a substrate.

[0050]FIG. 9a shows the circular saw 802 positioned above the substrateso that the saw can be lowered along the −y-axis to contact thesubstrate. The spinning saw can cut away substrate that it contacts,shown generally as 907. The saw can continue to be lowered through thesubstrate to a desired depth.

[0051]FIG. 9b shows an exemplary embodiment where the saw was loweredalong the −y-axis until the saw passed all the way through the substrate606. Other exemplary embodiments can cut through less than the entirethickness of the substrate, and/or make multiple passes to cut thedesired thickness. Regardless of the depth cut, the saw can then bemoved along the −x-axis for a desired distance. This is commonlyreferred to as a drag cut. When the saw has reached the desired distancealong the x-axis, it can be moved along the y-axis to cease contact withthe substrate. For example, FIG. 9c shows the saw having reached thedesired distance in the x direction. The saw can now be moved along they-axis away from the substrate.

[0052]FIG. 9d shows the substrate after the cutting performed in FIGS.9a-9 c.

[0053]FIG. 9e shows material being removed from the opposite side of thesubstrate as shown in FIGS. 9a-9 c. In this exemplary embodiment, thesubstrate has been maintained in the original orientation and the saw802 is being used from the opposite side of the substrate.Alternatively, other exemplary embodiments can flip or otherwisereposition the substrate to reorient the second surface adjacent to thesaw or other cutting device. As shown, the first surface to be cutcomprised the thin film side, however, either side can be cut first. Forexample, in other exemplary embodiments, the backside can be cut first,then the thin film side.

[0054] In the exemplary embodiments shown in FIGS. 9a-9 e, the saw wasmoved along a single axis at a time and a single pass was made throughthe substrate from a given side, in other exemplary embodiments the sawcan be moved in both the x and y axes simultaneously. Additionally, thedescribed embodiments show the saw cutting through the substrate in asingle pass from each side. Other exemplary embodiments can makemultiple passes from one or both of the sides to remove a desired amountof substrate. Additionally, some exemplary embodiments can achieve thecut(s) by moving the substrate and leaving the saw stationary, whileothers can move the saw and still others can utilize a combination ofmovements.

[0055] Utilizing a drag cut, as shown in FIGS. 9b and 9 e allows theformation of slots of any desired length. This can be advantageous asgreater slot length can increase printer speed. The greater slot lengthcan increase printer speed, by among other things, allowing the printhead to cover a wider swath on the print media per pass. The use of thecircular saw can also decrease the time required to make each slot. Withsome existing embodiments, a saw cut from one side of the substrate caneasily be accomplished in about 1 to 2 seconds. This is much faster thanexisting technology that takes about 8 to 10 seconds or more to make aslot. Further, in these embodiments, increasing the slot length addsvery little time to this method whereas existing methods takesubstantially longer to produce longer slots. In some embodiments, theslots can be as long as desired while maintaining a high aspect ratio asdescribed above.

[0056]FIGS. 10a-10 e show another exemplary embodiment for forming aslot. In this embodiment, the saw is utilized to make a cut in one sideof the substrate and another technique, other than sawing, is utilizedto remove material from the opposite side.

[0057]FIG. 10a shows substrate being removed from the first side 610 ofthe substrate 606. In this exemplary embodiment, the substrate is beingremoved, generally at 1001, with a laser machine 1002. The laser machineis emitting a laser beam 1004. This process is commonly referred to aslaser ablation or laser machining. Other exemplary embodiments can usewet or dry etching and rotating drill bits among others. It can beadvantageous to use these processes in combination with sawing, becauseamong other reasons, these processes tend to decrease in efficiency asthey remove material at greater depths. For example, in one embodiment,a laser cut can become much slower as the depth increases because debrisbuilds up in the trench as the depth increases. With the describedembodiments, a shallow trench can be created with the laser or otherprocess and the majority of the thickness of the substrate can beremoved with the saw from the other side.

[0058]FIG. 10b shows the substrate with a portion removed by the laser.In this embodiment, the laser has removed approximately 50 percent ofthe thickness of the substrate. Other exemplary embodiments can removefrom less than about 1% to about 100% of the thickness of the substrate.

[0059]FIG. 10c shows the saw 802 contacting the substrate from thesecond surface 612. In this exemplary embodiment, the saw cut isintersecting, or combining with portions, of the laser cut. As can beseen in FIG. 10d at least a portion of the combined cutting and removingmakes a slot that passes entirely through the thickness of thesubstrate. In this exemplary embodiment, the second cut was made with asingle chop cut of the saw. Other exemplary embodiments can utilize oneor more chop cuts combined with one or more drag cuts to remove thesubstrate. Also, in some embodiments, the laser process can occur firstand the saw cut second as shown. Alternatively, in some embodiments, thesaw cut can be first and the laser second. Further, the laser processcan be used on the thin film side with the saw used on the backside orconversely, the laser can be used on the backside and the saw cut on thethin film side, in some embodiments.

[0060] In a further embodiment, sand drilling can be utilized to removematerial from the backside and the saw cut utilized to remove materialfrom the front side. In this exemplary embodiment, as with thosediscussed previously, the order of the processes is interchangeable.

[0061]FIGS. 11a-11 e show a further exemplary embodiment for formingslot(s) in the substrate. FIGS. 11a and 11 b show the saw making a chopcut to remove material from the first side, in one embodiment. FIG. 11cshows the cut after the saw has been removed from the substrate, inanother embodiment. In another embodiment, FIG. 11d shows a rotatingdrill bit 1102 being used to remove material from the second side. Thedrill bit can spin on an axis c generally perpendicular to the firstsurface of the substrate. In this embodiment, when the drill bit entersthe substrate this axis also enters the substrate. The drill bit shownhere is cylindrical, but other shapes including conical bits amongothers can be used. FIG. 11e shows the slot after completion of theabove processes. In this exemplary embodiment, it can be preferable tocut with the saw from the thin film side and to remove material with thedrill from the backside. In some embodiments, the use of the drill toremove material from the substrate either before or after sawing candecrease the concentration of stress forces on specific areas of thesubstrate when compared to saw cutting by itself. For example, after thedrill bit removes material in FIG. 11d the resultant angle formed at theend of the slots can be maintained at approximately 90 degrees orgreater, in some embodiments. This angle is measured relative to thesubstrate and is denoted by the symbols θ and δ.

[0062] The described embodiments have shown only steps that removematerial in the slot formation process. Other exemplary embodiments canalso have steps which add material. For example, a cut can be made froma first side followed by a deposition step and then an etching step fromthe second side to form the finished slot. Other exemplary embodimentscan utilize additional finish steps to improve the quality of the slot.For example, a saw cut can be used to form a first trench from one sideand another saw cut forming a second trench to form a slot, in oneembodiment. In another embodiment, sand drilling can then be used tofurther polish or smooth the slot.

CONCLUSION

[0063] The described embodiments can provide methods and systems forforming slots in a semiconductor substrate. The slots can be formed bymaking a saw cut from one side of the substrate and then removingmaterial by various means from a second opposite side of the substrate.The slots can be inexpensive and quick to form. They can be made as longas desirable and have beneficial strength characteristics that canreduce die fragility and allow slots to be positioned closer together onthe die.

[0064] Although the invention has been described in language specific tostructural features and methodological steps, it is to be understoodthat the invention defined in the appended claims is not necessarilylimited to the specific features or steps described. Rather, thespecific features and steps are disclosed as preferred forms ofimplementing the claimed invention.

What is claimed is:
 1. A method of fabricating a fluid feed slot in aprint head substrate, comprising: making a cut into a first surface of asubstrate using a cutting disk having a generally planar surface that isoriented generally perpendicular to the first surface; and, removingmaterial from a second surface of the substrate effective to form, incombination with said cut, a slot at least a portion of which passesentirely through the substrate.
 2. The method of claim 1, wherein saidmaking a cut into the first surface comprises making a cut into a thinfilm side of the substrate.
 3. The method of claim 1, wherein saidmaking a cut into the first surface comprises making a cut with the sawblade being moved in both the x and y directions relative to thesubstrate.
 4. The method of claim 1, wherein said making a cut into thefirst surface comprises making a cut into a backside of the substrate.5. The method of claim 1, wherein said making a cut with the diskcomprises making a cut with a circular saw.
 6. The method of claim 1,wherein said making a cut into the first surface comprises making a cutat least a portion of which extends through the substrate.
 7. The methodof claim 1, wherein said making a cut comprises making multiple passeswith the disk to cut a desired thickness.
 8. The method of claim 1,wherein said removing comprises making a second cut with a disk.
 9. Themethod of claim 1, wherein said removing comprises one or more of: sanddrilling, dry etching, wet etching, and drilling with a rotary drillbit.
 10. The method of claim 1, wherein said removing and said cuttingform a slot having end walls, and wherein said removing forms a firstportion of the end walls and said cutting forms a second portion of theend walls and wherein the first and second portions of each of the endwalls meet at angle greater than or equal to ninety degrees relative tothe substrate.
 11. The method of claim 1, wherein said act of removingis performed before said act of making a cut.
 12. A fluid ejectingdevice having a substrate made according to the method of claim
 1. 13. Amethod of forming a fluid handling slot in a semiconductor substratehaving first and second opposing surfaces and microelectronicsintegrated therein, comprising: cutting with a circular saw into asemiconductor substrate into one of the first and second surfaces; and,creating a trench in the semiconductor substrate into the other of thefirst and second surfaces to form in combination with said cutting aslot through the substrate.
 14. The method of claim 13, wherein saidcreating comprises cutting with a circular saw.
 15. The method of claim14, wherein said cutting comprises moving the circular saw in a firstdirection substantially perpendicular to the first surface.
 16. Themethod of claim 15, wherein said cutting further comprises moving thecircular saw in a second direction substantially parallel to the firstsurface.
 17. The method of claim 15, wherein said cutting furthercomprises moving the circular saw in a first direction substantiallyperpendicular to the first surface and in a second directionsubstantially parallel to the first surface.
 18. The method of claim 14,wherein said cutting comprises making multiple passes with the circularsaw.
 19. The method of claim 13, wherein said act of cutting occursprior to said act of creating.
 20. The method of claim 13, wherein saidcreating comprises etching substrate material.
 21. The method of claim13, wherein said creating comprises sand drilling substrate material.22. The method of claim 13, wherein said creating comprises drillingsubstrate material with a rotary bit.
 23. A fluid ejecting device havinga substrate made according to the method of claim
 13. 24. A method offorming slots in a semiconductor substrate containing microelectronicscomprising: removing material from a first side of the semiconductorsubstrate; and, removing material from a second side of thesemiconductor substrate wherein removing material from at least one ofthe first and second sides is accomplished with a mechanical cuttingtool having a circular cutting disk revolving around an axis and wherethe cutting disk cuts the semiconductor substrate with the axisgenerally parallel to the first and second surfaces of the semiconductorsubstrate, and wherein at least portions of the removing from the firstside and removing from the second side form a slot through the substratematerial.
 25. The method of claim 24, wherein both removing from a firstside and removing from a second side comprise cutting the substrate withthe cutting tool.
 26. The method of claim 24, wherein removing materialfrom a first side comprises removing material from the substrate by wetetching the first side.
 27. The method of claim 24, wherein removingmaterial from a first side and removing material from a second side forma slot having an aspect ratio of greater than or equal to
 1. 28. Themethod of claim 24, wherein removing material from a first side andremoving material from a second side form a slot having an aspect ratioin a range from about 1 to about
 22. 29. The method of claim 24, whereinremoving material from a first side and removing material from a secondside form a slot having an aspect ratio of greater than or equal to 22.30. The method of claim 24, wherein removing material from a first sidecomprises removing material by dry etching the first side.
 31. Themethod of claim 24, wherein removing material from a first sidecomprises removing material by laser machining a first side.
 32. A fluidejecting device having a substrate made in accordance with the method ofclaim
 24. 33. A method of forming slots in a semiconductor substratehaving first and second opposing surfaces comprising: removing materialfrom either a first or second surface; and, making a mechanical cut intothe other of the first or second surface effective to form incombination with said removing, a slot at least a portion of whichpasses entirely through the substrate, wherein the slot has an aspectratio greater than or equal to one.
 34. The method of claim 33, whereinsaid removing occurs prior to making the mechanical cut.
 35. The methodof claim 33, wherein said making a mechanical cut occurs prior to saidremoving.
 36. The method of claim 33, wherein said removing comprisesone of dry etching, wet etching, cutting, or laser ablating thesubstrate.
 37. The method of claim 36, wherein said removing comprisesremoving thin film material from the first surface.
 38. The method ofclaim 33, wherein said removing comprises sand drilling, and whereinsaid sand drilling removes material from a backside.
 39. The method ofclaim 38, wherein said sand drilling occurs prior to said making of themechanical cut.
 40. A fluid ejecting device having a substrate made inaccordance with the method of claim
 33. 41. A method of forming slots ina semiconductor substrate having first and second opposing surfacescomprising: making a cut into a first surface of a semiconductorsubstrate using a cutting tool, wherein the cutting tool has an axis ofrotation generally parallel to the first surface; and, removing materialfrom a second surface of the semiconductor substrate effective to form,in combination with said cut, a slot at least a portion of which passesentirely through the semiconductor substrate.
 42. A fluid ejectingdevice having a substrate made in accordance with the method of claim41.
 43. A method of forming slots in a semiconductor substrate havingfirst and second opposing surfaces comprising: making a cut into a firstsurface of a semiconductor substrate using a cutting tool, wherein thecutting tool has an axis of rotation that is not perpendicular to thefirst surface; and, removing material from a second surface of thesemiconductor substrate effective to form, in combination with said cut,a slot at least a portion of which passes entirely through thesubstrate.
 44. A fluid ejecting device having a substrate made inaccordance with the method of claim
 43. 45. One or morecomputer-readable media having computer readable instructions thereonwhich, when executed by a computer, cause the computer to: causematerial to be removed from either the first or second surfaces of asemiconductor substrate; and, cause a mechanical cut to be made into theother of the first or second surfaces of a semiconductor substrateeffective to form in combination with said removing, a slot at least aportion of which passes entirely through the substrate.